Revisions - Svenska kraftnät · 12.5.3 Socket coupling ... 12.4.1 Ball coupling Ball fittings for...

TEKNISK RIKTLINJE 2012-04-02 TR 05-12E utg 2

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Revisions Notes Changed note Date

1 (A) Changed template 09 / 07 / 2008

2 Changed template. Clause 12.5.4.1 hot-rolled steel added . Clause 12.5.4.2, 12.5.2.4, 12.5.3.4, 12.5.4.4, 12.5.5.4, 12.5.6.4, 12.5.7.4 and 12.5.8.4 “shall be thermally designed to resist the fault current of 40 kA – 1 sec” added. Clause 12.5.8.2 nuts shall be locked with 2 punches, added. Clause 12.9.2.6 revised. 12.9.3 added.

02 / 04 / 2012


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Contents

12.1 References ................................................................................................................. 6

12.2 Scope .......................................................................................................................... 7

12.3 Definitions ................................................................................................................. 7

12.4 Description ............................................................................................................... 8

12.4.1 Ball coupling................................................................................................ 8

12.4.2 Socket coupling ........................................................................................... 8

12.4.3 Clevis-Tongue fitting .................................................................................. 8

12.4.4 Yoke plate .................................................................................................... 8

12.4.5 Turnbuckle ................................................................................................... 8

12.4.6 Coupling bolt ............................................................................................... 8

12.4.7 Power arc protection device ....................................................................... 8

12.5 Requirements ........................................................................................................... 8

12.5.1 General ........................................................................................................ 8

12.5.1.1 Marking ........................................................................................ 8

12.5.1.2 Mechanical requirements ............................................................. 9

12.5.2 Ball coupling............................................................................................... 10

12.5.2.1 Material ....................................................................................... 10

12.5.2.2 Design .......................................................................................... 10

12.5.2.3 Mechanical requirements ........................................................... 10

12.5.2.4 Electrical requirements .............................................................. 10

12.5.3 Socket coupling .......................................................................................... 10

12.5.3.1 Material ....................................................................................... 10

12.5.3.2 Design .......................................................................................... 10



12.5.4 Clevis - tongue coupling ............................................................................ 11

12.5.4.1 Material ....................................................................................... 11

12.5.4.2 Design .......................................................................................... 11



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12.5.5 Yoke Plate ................................................................................................... 11

12.5.5.1 Material ....................................................................................... 11

12.5.5.2 Design .......................................................................................... 12



12.5.6 Turnbuckles ................................................................................................ 12

12.5.6.1 Material ....................................................................................... 12

12.5.6.2 Design .......................................................................................... 12



12.5.7 Coupling bolt .............................................................................................. 13

12.5.7.1 Material ....................................................................................... 13

12.5.7.2 Design .......................................................................................... 13



12.5.8 Power arc protection device ...................................................................... 13

12.5.8.1 Material ....................................................................................... 13

12.5.8.2 Design .......................................................................................... 13



12.6 Type test ................................................................................................................... 14

12.6.1 General ....................................................................................................... 14

12.6.2 Dimensions ................................................................................................. 15

12.6.3 Thickness of zinc coating ........................................................................... 15

12.6.4 Strength ...................................................................................................... 15

12.6.4.1 Fittings ......................................................................................... 15

12.6.4.2 Yoke plate ..................................................................................... 15

12.6.4.3 Arcing horn .................................................................................. 16

12.6.5 Fault current .............................................................................................. 16

12.6.6 Corona ........................................................................................................ 16

12.7 Sample test .............................................................................................................. 17

12.7.1 General ....................................................................................................... 17

12.7.2 Dimensions ................................................................................................. 17

12.7.3 Thickness of zinc coating ........................................................................... 17

12.7.4 Strength ...................................................................................................... 18


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12.8 Routine test ............................................................................................................. 18

12.9 Delivery .................................................................................................................... 18

12.9.1 General ....................................................................................................... 18

12.9.2 Documentation ........................................................................................... 18

12.9.2.1 Assembly drawing ...................................................................... 18

12.9.2.2 List of material ............................................................................ 18

12.9.2.3 Manufacturing process ............................................................... 18

12.9.2.4 Quality system ............................................................................. 19

12.9.2.5 Installation instructions ............................................................. 19

12.9.2.6 Reports ......................................................................................... 19

12.9.3 Transport and storing ............................................................................... 19

12.10 Installation............................................................................................................... 19

12.11 Tables ...................................................................................................................... 20

Table 1 Strength classes of fittings ....................................................................... 20

Table 2 Dimensions of clevis-tongue fittings ....................................................... 20

12.12 Figures ..................................................................................................................... 21

Figure 1 Dimensions of clevis-tongue fittings .......................................... 21

Figure 2 Yoke plate test load arrangement ..............................................22


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12.1 References

Note that standards, regulations etc. which are referred to in these guidelines are subject to continuous change and can be withdrawn, revised or replaced. It is the obligation that the contractor immediately will inform the client of such changes. IEC 60471 Dimensions of clevis and tongue couplings of string insulator units

IEC 61467 Insulators for overhead lines with a nominal voltage above 1 000 V- AC power arc tests on insulator sets

SS 424 12 11 Overhead line material - Clevis and tongue couplings, dimensions

SS-EN 10045-1 Metallic materials - Charpy impact test - Part 1: Test method

SS-EN 20898-2 Mechanical properties of fasteners - Part 2: Nuts with specified proof load values - Coarse thread

SS-EN 50341 Overhead electrical lines exceeding 45 kV (AC)

SS-EN 60372 Locking devices for ball and socket couplings of string insulator units - Dimensions and tests

SS-EN 60383-1 Insulators for overhead lines with a nominal voltage above 1 000 V- Part 1: Ceramic or glass insulator units for a.c. systems - Definitions, test methods and acceptance criteria

SS-EN ISO 898-1 Mechanical properties of fasteners made of carbon steel and alloy steel -- Part 1: Bolts, screws and studs

SS-EN ISO 1234 Split pins

SS-EN ISO 1461 Hot dip galvanized coatings on fabricated iron and steel articles - Specifications and test methods

SS-EN ISO 6506-1 Metallic materials - Brinell hardness test - Part 1: Test method (ISO 6506-1:1999)

SS-EN ISO 9001 Quality management systems - Requirements

SS-EN ISO 10684 Fasteners Hot dip galvanized coatings (ISO 10684:2004)

SS-IEC 60120 Dimensions of ball and socket couplings of string insulator units

SS-ISO 272 Fasteners -- Hexagon products -- Widths across flats

SS-ISO 965-4 ISO general purpose metric screw threads – Tolerances - Part 4: Limits of sizes for hot-dip galvanized external


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screw threads to mate with internal screw threads tapped with tolerance position H or G after galvanizing

SS-ISO 2178 Non-magnetic coatings on magnetic substrates - Measurement of coating thickness - Magnetic method

SS-ISO 3508 Thread run-outs for fasteners with thread in accordance with ISO 261 and ISO 262

SS-ISO 5455 Technical drawings - Scales

SvK TR 05-10E Technical guidelines – Insulator sets

SvK TR 08E Technical guidelines – Documentation

12.2 Scope

These guidelines are applicable to fittings which are to be used in insulator sets according to SvK TR 05-10E for overhead lines and comprise design and testing. The intention of the specification is to guarantee satisfactory performance of the insulator fittings during the lifetime of the overhead line.

12.3 Definitions

Technical terms and definitions used in these guidelines: Insulator set Device for insulating conductors either in suspension or tension. Insulator string The insulating part of the insulator set consisting of one or more insulators joined together. Highest voltage for equipment The highest phase-to-phase voltage for which the equipment is designed. The highest

voltage for equipment is designated Um in this document.

Corona extinction voltage The voltage where no corona is visible when the voltage is reduced from a level with visible corona. Fault current

The greatest short duration current which is caused by either a short-circuit (Ik) or

earth fault (3I0)


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12.4 Description

12.4.1 Ball coupling Ball fittings for facilitating a connection to the socket on the cap side of disc insulators.

12.4.2 Socket coupling Socket fittings for facilitating a connection to the ball on the pin side of disc insulators.

12.4.3 Clevis-Tongue fitting Fittings with a clevis and tongue which can be connected by means of either a bolt or a pin.

12.4.4 Yoke plate Fitting for separating twin insulator strings and twin or triple conductors at a predetermined fixed distance.

12.4.5 Turnbuckle Fitting for adjusting the distance between the support and the insulator string or the insulator string and the conductor.

12.4.6 Coupling bolt Means of joining fittings with a clevis and tongue coupling.

12.4.7 Power arc protection device Fitting for the protection of insulator strings and conductors from power arcs and for distributing the electrical field.

12.5 Requirements

12.5.1 General Fittings shall be able to withstand the mechanical stresses which can occur during transport, handling and installation at temperatures as low as –40 °C, in addition to the mechanical stresses which can occur during the lifetime of the overhead line at temperatures from -50 °C to +100 °C.

12.5.1.1 Marking Fittings shall be marked with raised or indented/stamped characters with a minimum height of 3 mm as follows:

Trademark of the manufacturer

Type or catalogue number

Insulator designation

Bolts and nuts to be marked in accordance with SS-EN ISO 898-1 och SS-EN 20898-2.


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Year of manufacture

12.5.1.2 Mechanical requirements Insulator fittings shall conform to the mechanical requirements of SS-EN 50341. When designing/dimensioning insulator fittings by means of stress calculations the following additional requirements shall be fulfilled.

The combined stress (comb) of tension, bending and shear shall be less than the

characteristic strength fuk at a load equivalent to Fuk in accordance with SS-EN

50341:11.6.SE.1.1.

The combined stress (comb) of tension, bending and shear shall be less than the

characteristic strength fyk at a load equivalent to 1.1 times the load Rd in accordance

with SS-EN 50341:11.6.SE.1.1.

The combined stress (comb) of tension, bending and shear shall be calculated

according to the formula:

2223 yxyxcomb

When testing fittings made from steel or aluminium permanent deformation due to

tension, bending and shear stress may not occur at a load less than Fdef where:

Fdef = 1,1•Rd

Where Rd is the dimensioning load in the serviceability limit state in accordance with

SS-EN 50341:11.6.SE.1.1.

The breaking load (Fu) achieved during testing shall, for fittings made from steel and

aluminium which have been statistically tested in accordance with SS-EN 60383-1,

exceed Fuk.

The breaking load (Fu1) achieved during testing shall for other fittings exceed:

Ful = 1,1•Fk

Definitions

Fuk = The characteristic ultimate tensile strength given in regulations for the material

concerned.

fyk = The characteristic yield stress given in regulations for the material concerned.

Fdef = Minimum required test deformation load

Fk = Specified minimum failing load

Fu = Achieved test breaking load

Fu1 = Achieved test breaking load

Rd = Dimensioning load in the serviceability limit state


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12.5.2 Ball coupling

12.5.2.1 Material Ball couplings shall be made from forged steel and be hot-dip galvanised. The thickness of the zinc layer shall conform to the requirements of SS-EN ISO 1461 Table 2 and 3.

The impact strength of the forged steel shall be a minimum of 27 J at 0 C when tested in accordance with SS-EN 10045-1.

The rupture strength Rm for test specimens taken from the manufactured part shall

not exceed 700 MPa.

12.5.2.2 Design Balls on the end of pins shall conform to SS-IEC 60120. Attachments for arcing horns shall have two holes 14 mm diameter spaced at 32 mm centres. Other fittings shall be connected by either a tongue or a clevis coupling in accordance with Clause 12.5.4.2.

12.5.2.3 Mechanical requirements The ball coupling strength shall be equal to the minimum strength of the insulator string for which the ball coupling is intended and also conform to the requirements of 12.5.1 regarding allowable stress. For deformation and failing loads see Table 1.

12.5.2.4 Electrical requirements Ball couplings shall be thermally designed to resist the fault current of 40 kA -1 sec. Welding shall not occur between contact surfaces when tested in accordance with Clause 12.6.5. The peak value of the fault current shall be a minimum of 2,3 times the r.m.s value.

12.5.3 Socket coupling

12.5.3.1 Material Socket couplings shall be made from forged steel or malleable iron and be hot-dip galvanised. The thickness of the zinc layer shall conform to the requirements of SS-EN ISO 1461 Table 2 and 3.



not exceed 700 MPa.

12.5.3.2 Design Sockets shall conform to SS-IEC 60120. Size 16 mm shall be type 16A. Locking devices in accordance with SS-EN 60372 shall be used as retaining devices for ball couplings in sockets. Attachments for arcing horns shall have two holes 14 mm diameter spaced at 32 mm centres. Other fittings shall be connected by either a tongue or a clevis coupling in accordance with Clause 12.5.4.2.


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12.5.3.3 Mechanical requirements The socket coupling strength shall be equal to the minimum strength of the insulator string for which the socket coupling is intended and also conform to the requirements of 12.5.1 regarding allowable stress. For deformation and failing loads see Table 1.

12.5.3.4 Electrical requirements Socket couplings shall be thermally designed to resist the fault current of 40 kA -1 sec. Welding shall not occur between contact surfaces when tested in accordance with Clause 12.6.5. The peak value of the fault current shall be a minimum of 2,3 times the r.m.s. value.

12.5.4 Clevis - tongue coupling

12.5.4.1 Material Clevis-tongue couplings shall be made from forged, hot-rolled steel or malleable iron and be hot-dip galvanised. The thickness of the zinc layer shall conform to the requirements of SS-EN ISO 1461 Table 2 and 3.



not exceed 700 MPa.

12.5.4.2 Design Clevis-tongue couplings shall have dimensions as given in SS 424 12 11, IEC 60471, or Table 2 and Figure 1. Round holes for coupling bolts/pins shall be perfectly true with straight sides and through the whole coupling. The coupling shall be formed of one piece of materiel.

12.5.4.3 Mechanical requirements The clevis-tongue coupling strength shall be equal to the minimum strength of the insulator string for which the clevis-tongue coupling is intended and also conform to the requirements of 12.5.1 regarding allowable stress. For deformation and failing loads see Ttable 1.

12.5.4.4 Electrical requirements The clevis-tongue couplings shall be thermally designed to resist the fault current of 40 kA -1 sec. Welding shall not occur between contact surfaces when tested in accordance with Clause 12.6.5. The peak value of the fault current shall be a minimum of 2,3 times the r.m.s. value.

12.5.5 Yoke Plate

12.5.5.1 Material Yoke plates shall be made from forged steel and be hot-dip galvanised. The thickness of the zinc layer shall conform to the requirements of SS-EN ISO 1461 Table 2 and 3.



not exceed 700 MPa.


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12.5.5.2 Design Yoke plates shall have coupling dimensions in accordance with SS 424 12 11, IEC 60471, or Table 2 and Figure 1. Round holes for coupling bolts/pins shall be perfectly true with straight sides. Yokes for insulator strings shall be so designed that the distance between the insulator sheds will be at least 100 mm. Yokes for twin and triple bundle conductors shall be so designed that the distance between sub-conductors will be 450 mm up to and including a conductor diameter of 32 mm and 600 mm for conductor diameter greater than 32 mm.

12.5.5.3 Mechanical requirements The strength of the yoke plate shall be equal to the minimum strength of the insulator string for which the yoke plate is intended and also conform to the requirements of 12.5.1 regarding allowable stress. For deformation and failing loads, see Table 1.

12.5.5.4 Electrical requirements Yoke plates shall be thermally designed to resist the fault current of 40 kA -1 sec. Welding shall not occur between contact surfaces when tested in accordance with Clause 12.6.5. The peak value of the fault current shall be a minimum of 2,3 times the r.m.s. value.

12.5.6 Turnbuckles

12.5.6.1 Material Turnbuckles shall be made from forged steel and be hot-dip galvanised. The thickness of the zinc layer shall conform to the requirements of SS-EN ISO 1461 Table 2 and 3. The thickness of the zinc layer on threaded parts shall conform to the requirements of SS-ISO 965-4.



not exceed 700 MPa.

12.5.6.2 Design Turnbuckles shall have coupling dimensions in accordance with SS 424 12 11, IEC 60471, or Table 2 and Figure 1. Round holes for coupling bolts/pins shall be perfectly true with straight sides. Turnbuckles shall provide a minimum length adjustment of 150 mm. Adjustable parts shall be locked to prevent unwinding. Threaded parts shall be greased with corrosion protective grease.

12.5.6.3 Mechanical requirements The strength of the turnbuckle shall be equal to the minimum strength of the insulator string for which the turnbuckle is intended and also conform to the requirements of 12.5.1 regarding allowable stress. For deformation and failing loads, see Table 1.

12.5.6.4 Electrical requirements Turnbuckles shall be thermally designed to resist the fault current of 40 kA -1 sec. The current density in threaded parts shall not exceed 70 A/mm2. Welding shall not occur between contact surfaces when tested in accordance with Clause 12.6.5. The peak value of the fault current shall be a minimum of 2,3 times the r.m.s. value.


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12.5.7 Coupling bolt

12.5.7.1 Material Coupling bolts shall be made from forged steel and be hot-dip galvanised. The thickness of the zinc layer shall conform to the requirements of SS-EN ISO 1461 Table 2 and 3. Split pins shall be made from austenitic stainless steel. The impact strength of coupling bolts made from forged steel shall be a minimum of 27

J at 0 C when tested in accordance with SS-EN 10045-1.

12.5.7.2 Design The coupling for fittings shall consist of a bolt and nut. Fitting couplings shall be designed to have:

A head with a minimum of two parallel flanges. A cylindrical smooth part for contact with the body of the tongue or clevis coupling. A section with metric threads for installation of the nut. If the nut is not provided with metallic locking a suitable size hole for a split pin should be provided.

Threads shall be in accordance with SS-EN ISO 10684 with thread run-outs in accordance with SS-ISO 3508.

Split pins shall be designed in accordance with SS-EN ISO 1234.

The spanner to fit the head and nuts of fitting couplings shall have a width across flats in accordance with SS-ISO 272.

12.5.7.3 Mechanical requirements The strength of the coupling bolt shall be equal to the minimum strength of the coupling for which the turnbuckle is intended and shall also conform to the requirements of 12.5.1 regarding allowable stress. For deformation and failing loads, see Table 1.

12.5.7.4 Electrical requirements Coupling bolts shall be thermally designed to resist the fault current of 40 kA – 1 sec. Welding shall not occur between contact surfaces when tested in accordance with Clause 12.6.5. The peak value of the fault current shall be a minimum of 2,3 times the r.m.s. value.

12.5.8 Power arc protection device

12.5.8.1 Material Power arc protection devices shall be made from steel and be hot-dip galvanised. Should steel tubes be used for power arc protection devices, both the internal and external surfaces of the tubes shall be hot-dip galvanised. The thickness of the zinc layer shall for both external and internal surfaces conform to the requirements of SS-EN ISO 1461 Table 2 and 3.

12.5.8.2 Design It shall be possible to install power arc protection devices on assembled insulator sets. In addition they shall be so designed as to require a minimum of space on the supports. The attachment of arcing rings shall be on one side and be so designed that disc

insulators of the insulator string are able to incline at an angle ° in accordance with SS-IEC 60120 Annex A without damaging the glass/porcelain portion of any insulator disc.


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Attachment to fittings shall be one-sided and designed with two M12 bolts spaced at 32 mm centres. The bolts shall be attached to the power arc protection device in such a way that they are impossible to drop accidentally. Nuts shall be locked with two punches. Bolts shall conform to the requirements of property class 8.8 in accordance with SS ISO 889-1. Nuts shall conform to the requirements of property class 8 in accordance with SS-EN 20898-2 and have a width across flats in accordance with SS-ISO 272. Welds connecting the attachment arm to the arc ring shall be complete penetration welds. A distance of 45 mm between the arcing ring and the insulator shead is desirable.

12.5.8.3 Mechanical requirements Power arc protection devices shall withstand a load of 1500 N, acting at an arbitrary point, without being deformed. Power arc protection devices subject to fault current shall not be deformed by their own dead weight.

12.5.8.4 Electrical requirements Fault current

Power arc protection devices shall trap power arcs over the insulator string and divert them outwards. Power arc protection devices shall be thermally designed to resist the fault current of 40 kA – 1 sec, with a current density not exceeding 80 A/mm2. Welding shall not occur between the power arc protection devices contact surface and the fittings. The peak value of the fault current shall be a minimum of 2,3 times the r.m.s. value. Power arc protection devices shall conform to the requirements of IEC 61467 Clause 12.4 together with the additional test requirements that are specified in 12.6.5 contained herein.

Corona

Power arc protection devices shall, in a complete insulator set, conform to the requirements of SvK TR 05-10E Clause 10.5.5.4.

Voltage distribution

Power arc protection devices shall be so designed that the voltage distribution over the insulators is improved and that, in the case of an insulator string with disc insulators, the voltage does not exceed 20 kV over each individual insulator.

12.6 Type test

12.6.1 General Unless otherwise agreed type tests shall be performed in accordance with Clauses 12.6.2-12.6.6 on five test samples. The tests shall be conducted in such a way that neither the method nor the equipment affects the result.


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12.6.2 Dimensions The intention of this test is to verify that the fittings fulfil the requirements in accordance with Clauses 12.5.2.1, 12.5.3.1, 12.5.4.1, 12.5.5.1, 12.5.6.1, 12.5.7.1 and 12.5.8.1 in addition to being in accordance with the manufacturers drawings regarding measurements.

12.6.3 Thickness of zinc coating The intention of this test is to verify that the fittings fulfil the zinc coating thickness requirements in accordance with Clauses 12.5.2.1, 12.5.3.1, 12.5.4.1, 12.5.5.1, 12.5.6.1, 12.5.7.1 and 12.5.8.1. The tests shall be performed in accordance with SS-ISO 2178. Each sample shall be subject to, depending on size, 3 to 10 measurements. The points of measurement shall be evenly and randomly distributed over the entire sample surface.

12.6.4 Strength

12.6.4.1 Fittings The intention of this test is to verify that the fittings conform to the requirements of Clauses 12.5.2.3, 12.5.3.3, 12.5.4.3, 12.5.6.3, and 12.5.7.3. The tests shall be performed in a tensile testing machine. Every test sample shall be subjected to the deformation load in accordance with Table 1 and be checked regarding permanent deformation. After all checks have been completed the load shall be increased until failure occurs. Fittings shall not have any permanent deformation when checked. Fittings shall fulfil the following requirements regarding failing load:

TT SBKX *2,1

Where

TX = Average value of the type test results

MFL = Specified minimum failing load

T = Standard deviation for the type test results.

In addition hardness shall be tested in accordance with SS-EN ISO 6506-1.

12.6.4.2 Yoke plate The intention of this test is to verify that the yoke plate fulfils the requirements in accordance with Clause 12.5.5.3. The test shall be performed in a tensile testing machine. For testing the test specimen shall be mounted in accordance with Figure 2. Every test specimen shall be subjected to the deformation load in accordance with Table 1 and be checked regarding permanent deformation. After all checks have been completed the load shall be increased until failure occurs and be checked regarding yielding. Yoke plates shall not have any permanent deformation when checked. Yoke plates shall withstand the specified failing load without collapsing. In addition hardness shall be tested in accordance with SS-EN ISO 6506-1.


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12.6.4.3 Arcing horn The intention of this test is to verify that the arcing horn fulfils the requirements in accordance with Clause 12.5.8.3. The test shall be performed in a tensile testing machine or with a dead weight. Each test specimen shall be subjected to a load of 1500 N, which shall be applied at the most unfavourable point, and be checked regarding deformation. Arcing horns shall not have any permanent deformation when checked.

12.6.5 Fault current The intention of this test is to establish the capability of fittings to withstand fault current. The fittings shall be tested when assembled in a suspension insulator set in accordance with SvK TR 05-10E. Testing shall be performed in accordance with IEC 61467, test series X, test circuit A. The test load shall be 3 kN. Fittings for the insulator set shall fulfil the requirements of IEC 61467 Clause 12.4 with the following additions and alterations which shall be performed after the conclusion of the test series:

The zinc layer is not to be damaged

The creepage distance is not to be reduced due to damaged disc or composite insulators.

Exposure of white porcelain due to glaze scalds is not permitted on porcelain insulator discs.

All disc or composite insulator units in the string tested shall be tested to verify that they fulfil the electromechanical failing load requirement for porcelain insulators, the mechanical failing load requirement for toughened glass insulators and the specified mechanical load requirement for composite insulators.

All porcelain and toughened glass insulator units in the string tested shall be tested and shall pass a temperature cycling test in accordance with IEC 60383.

All disc or composite insulators in the string tested shall be tested to verify that they fulfil the requirement for wet power frequency withstand voltage.

12.6.6 Corona The intention of this test is to verify the corona extinction voltage in a fully assembled insulator string. The test shall be performed in accordance with SvK TR 05-10E Clause 10.6.5.


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12.7 Sample test

12.7.1 General Sample tests shall be carried out by the manufacturer on insulator fittings selected at random from the lot to be supplied. Test samples shall be supplied by the manufacturer free of charge to the client and shall not be included in the lot to be supplied. The size of the test samples are indicated in table below.

Lot size Sample size

N ≤ 300 Subject to agreement

300 < N ≤ 2000 4

2000 < N ≤ 5000 8

5000 < N ≤ 10000 12

The samples shall be subjected to testing in accordance with Clauses 12.7.2 to 12.7.4. Insulator fittings which have been submitted for test shall be discarded.

The manufacturer shall inform the client when sample tests shall be performed. Records from the sample tests shall be filed by the manufacturer and be shown to the client on request. In the case where any component does not comply with the requirements, re-testing shall be performed as below. If only one fitting, or part thereof, fails to comply with the sample test requirement, a new sample equal to twice the quantity originally submitted for that test shall be subject to re-testing. The re-testing shall comprise the test or tests in which failure occurred. If two or more fittings, or parts thereof, fail to comply with any of the sample tests, or if any failure occurs during re-testing, the complete lot shall be considered not to comply with the requirements. Provided that the cause of the failure can be clearly identified, the manufacturer may sort the lot to eliminate all the fittings with this defect. The sorted lot shall then be resubmitted for sample testing. The number then selected shall be three times the first quantity chosen for the test. The re-testing shall comprise the test or tests in which failure occurred in the original test. If any fitting, or part thereof of the sorted lot, fails during this re-testing, the complete lot shall be considered as not complying with the requirements.

12.7.2 Dimensions This test shall be performed in accordance with Clause 12.6.2.

12.7.3 Thickness of zinc coating This test shall be performed in accordance with Clause 12.6.3.


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12.7.4 Strength This test shall be performed in accordance with Clause 12.6.4.

12.8 Routine test

Fittings made of malleable iron shall be proof load tested. The tests shall be performed as a mechanical load test. A mechanical load of 50 % of the specified failing load shall be applied to the fitting. Fittings which show permanent deformation or cracks shall be discarded.

12.9 Delivery

12.9.1 General The client shall, according to these guidelines, approve the fittings before delivery. For approval the manufacturer shall show that the fittings conform to these guidelines. The manufacturer shall provide documentation in accordance with Clauses 12.9.2.1 to 12.9.2.7 inclusive for approval. The approval of drawings by the client does not release the manufacturer from his obligations regarding the fittings complying with these guidelines. All documentation shall be written in Swedish or English.

12.9.2 Documentation General requirements for documentation see SvK TR 08E.

12.9.2.1 Assembly drawing Each assembly drawing shall have a minimum of two views at an appropriate scale in accordance with SS-ISO 5455. On each drawing shall be given:

Type and/or catalogue number

Principal dimensions

The dimensions of the fitting with tolerances

All marking

Weight

List of materials

12.9.2.2 List of material Description of material in included parts.

12.9.2.3 Manufacturing process Description of the manufacturing process


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12.9.2.4 Quality system Quality system in accordance with SS-EN ISO 9001.

12.9.2.5 Installation instructions Installation instructions in Swedish or English with the required drawings.

12.9.2.6 Reports Reports in accordance with Clause 12.6-12.8.

12.9.3 Transport and storing The insulator set fittings shall be packed up in that way that they will not be damaged or fouled at transport, construction and storing.

12.10 Installation

Installation shall be performed in accordance with the installation instructions. The power arc nuts shall be locked with two punches.


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12.11 Tables

Table 1 Strength classes of fittings

Specified Deformation Insulator Breaking load Allprov load

class Fuk Fuk1 kraft Fdef kN kN kN kN

U 70 70 85 35 33,5

U 120 120 146 60 57,4

U 160 160 195 80 76,6

U 210 210 256 105 100,5

U 300 300 366 150 143,5

2 * U 210 420 512 210 201,0

2 * U 300 600 732 300 287,1

Table 2 Dimensions of clevis-tongue fittings

Breaking d e Bolt load a b c max min diameter kN mm mm mm mm mm mm

420 201 231 271 50 51 240,6

600 201 231 351 65 66 320,6


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12.12 Figures

Figure 1 Dimensions of clevis-tongue fittings

Dimensions given in Table 2

d

e

d

e

d

d

b

a

c

c


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Figure 2 Yoke plate test load arrangement

F

F

Shackle

Shackle

Chain link

F

F

Shackle

Shackle

Chain link

Revisions - Svenska kraftnät · 12.5.3 Socket coupling ... 12.4.1 Ball coupling Ball fittings for...

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Transcript of Revisions - Svenska kraftnät · 12.5.3 Socket coupling ... 12.4.1 Ball coupling Ball fittings for...